It has long been a feature of many types of compositions, including cosmetic compositions and those of other consumer products, that they comprise volatile solvents, often for the purpose, among others, of solubilising ingredients, for example perfume oils, within the composition. The presence of perfume oils within such cosmetic compositions is useful to mask unpleasant odours and to improve consumer acceptance of the composition through delivering a pleasant smell. Indeed, the sole purpose of some cosmetic compositions is the application of a pleasant odour to human or animal skin, hair, or other suitable substrates, by use of these perfume oils. However, for the most part, upon application of such a cosmetic composition containing a volatile solvent, in conjunction with a fragrance, there occurs an initial rapid evaporation of the volatile solvent. This results in a harsh, solvent odour, for example alcoholic odour, which can mask the fragrant impact and reduce consumer acceptance.
Although many attempts have been made to alter the volatility profiles of ingredients within compositions, and particularly within cosmetic compositions, containing volatile solvents, to date, these have mainly focused on altering the volatility profiles of the fragrant materials themselves. For example, it has been suggested that the addition of cyclic oligosaccharides to such cosmetic compositions can alter the volatility profile of the perfume oils giving a longer lasting effect to the fragrance of the cosmetic composition. Previous prior art in this area includes JP-A-50/63126 which discloses the use of perfume and cyclodextrin complexes for use in bath preparations; JP-A-7/241333 which discloses a long-lasting room deodorising composition containing a fragrance and cyclodextrin and U.S. Pat. No. 5,238,915 which discloses pH dependent perfume oil/cyclodextrin complexes within aromatic compositions.
It is now desired to alter the volatility profile of the solvents themselves within cosmetic compositions to, for example, delay the release of the solvent and to reduce the initial harsh solvent odour impact, for example alcoholic/ethanolic. Although some of the prior art cited above discloses compositions that contain cyclic oligosaccharides combined with volatile solvents within a cosmetic composition, they disclose only the durative effects that the addition of the cyclic oligosaccharide has on the release of the fragrance without specifically disclosing any affect that the cyclic oligosaccharide has on the volatility profile of the volatile solvent itself.
Surprisingly, it has now been found that cyclic oligosaccharides can be used within compositions, particularly cosmetic compositions, containing at least 50% volatile solvent to delay the release of volatile solvents and also to reduce the initial harsh ethanolic/alcoholic odour impact of an alcoholic or hydro-alcoholic cosmetic composition.
While not wishing to be bound by theory, it is believed that when cyclic oligosaccharides are added to a cosmetic composition comprising at least 50%, preferably from about 50% to about 99.9%, more preferably from about 60% to about 95%, even more preferably from about 65% to about 75%, by weight, of volatile solvent, the volatile solvent itself competes with the perfume oils for complexation in the cyclic oligosaccharide cavity. This results in some “in situ complexation” between the volatile solvent and the cyclic oligosaccharide. It is believed that the stability profile of this cyclic oligosaccharide:volatile solvent complex is such that there is a delay in the release of the volatile solvent from the composition when applied to a substrate. It is further believed that this results in a perceptible reduction in initial solvent release thus satisfying the consumer desire for a reduced initial harsh solvent odour, for example alcoholic odour, upon cosmetic composition application.